1. Field of the Invention
This invention relates to a universal bracket for holding objects in place in a mold for a poured wall. When the material poured in the mold for the wall sets up, the bracket is removed, and the object is embedded on the surface of the wall. More particularly, the invention relates to an improved bracket that is universal in that it has no preferred polarity during installation and has tab and slot interlocks designed to facilitate removal of the brackets from the wall after the poured material has set up.
2. Description of the Related Art
Simulated brick construction with concrete forming and fabrication of structures is becoming increasingly common in the construction of modern buildings. This is due to the fact that it is quite expensive to use the services of masons in order to build a true laid-up brick or masonry wall. With the scarcity of skilled workers today, the ability to fabricate a true brick or masonry wall is quite problematic. In order to get around these increased costs and problems, many construction companies have gone to the use of simulated brick building panels which are backed by concrete and positioned as required to form a wall, or structure, which has a simulated brick exterior appearance.
Construction of this type of wall has been improved recently by the use of brick, or object, retainers which are fastened to the inside surface of a vertical wall form or laid on the inside surface of a horizontal wall form. In this way, as the concrete is poured into the form, it flows around the back of the brick which is embedded in the outer surface of the structure. A recent bracket, or retainer, for holding bricks and objects in place in a wall form is described in U.S. Pat. No. 5,667,190 entitled "Object Bracket Holder For Concrete Forms." This bracket is superior to earlier mold forms. However, the bracket has a number of problems that make it difficult to use. First of all, the bracket is polarized in that each bracket must be oriented one way for its tabs and slots to engage an adjacent bracket. Second, the polarized brackets are difficult to remove from a finished pre-cast wall because the tabs, fastening the brackets together, fracture when the polarized bracket is pulled loose from the brick embedded in the wall. As a result, the polarized brackets tend to come off the wall, one or a few at a time, rather than as a complete set of brackets fastened together in the form. A third problem with the polarized bracket is that it can only be used to create whole or 1/2 brick overlap patterns in the brick masonry pattern. Conventional masonry patterns also include 1/3 and 1/4 brick overlay patterns as well.
FIG. 1 is an illustration of how the prior art polarized brackets of U.S. Pat. No. 5,667,190 are coupled to each other to create a half brick overlap pattern or a vertical brick pattern. Only the outline of the polarized bracket with tabs and slots are shown in FIG. 1. The details of the bracket and all the uses for such a bracket are described in U.S. Pat. No. 5,667,190 which, for purposes of illustrating how a thin brick bracket may be used in forms, is incorporated herein by reference.
The FIG. 1 illustration of the coupling of the polarized brackets is useful as it illustrates two of the significant problems with the design of the polarized bracket. The outline of the bracket in FIG. 1 illustrates the tabs and slots in top-side member 12, and right end member 14. Top side member 12, at positions approximately one-quarter length and three-quarter lengths down the length of the top side has a pattern of two tabs 16 and a slot 18. End wall 14 has a pattern of four slots 20 arranged in pairs. Each pair of slots 20 is spaced apart in manner to engage with tabs 16.
Bracket 22 in FIG. 1 illustrates the tab and slot patterns on left-end wall 24 and bottom side wall 26. Bottom side wall 26 has tabs 28 at 1/4 and 3/4 positions along the length of the side wall 26. Tabs 28 are flanked by a pair of slots 30. Left-end wall 24 of bracket 22 has two slots 32 that are engaged to couple with one of the other of tabs 28 of another bracket placed at 90-degrees relative to bracket 22.
An examination of the pattern of tabs and slots and their locations on the side walls and end walls indicates the polarized nature of the polarized bracket taught in U.S. Pat. No. 5,667,190. For example, a bottom side wall can only engage a top side wall, or a left-end wall of an adjacent bracket. Similarly, a top side wall 12 can only couple with a bottom side wall, such as 26, or a right end wall, such as 14. A side wall 26 cannot engage a similar side wall 26 of another bracket. Likewise, a side wall 12 cannot engage a similar side wall 12 on another bracket. Accordingly, the brackets in the prior art are polarized and can only be oriented for coupling with adjacent brackets, as shown in FIG. 1. This limits the flexibility of the patterns available in using the polarized brackets and also increases the time in assembling brick wall frames in that the brackets must be oriented in a particular direction before they will couple.
FIG. 1 also illustrates the problem of trying to strip a set of brackets as shown, from a finished wall. The stripping problem with the brackets in FIG. 1 is their configuration of tabs and slots places severe stress on the tabs when a user tries to pull a bracket from a finished pre-cast wall. Accordingly, the tabs snap off, and the user must pull each bracket one by one, or a few at a time, off the wall. The forces acting on the tabs can be understood by examining brackets 34, and 36 in FIG. 1. Assume that the concrete has set up. and that the pre-cast wall has been raised to a vertical position. The frame used in casting the wall has been removed. It is now necessary to remove the brackets adhering to the bricks and mortar between the bricks. A user would typically pry or lift away the right end 38 of bracket 34 free from the brick and the mortar joint. To peel or strip other brackets from the wall by lifting end 38 of bracket 34, adjacent brackets must remain hooked together. Bracket 34 will tend to rotate around abutment joint 40 where the left end of bracket 34 abuts the right end of bracket 42. The leverage of top side wall 44 of bracket 34 about fulcrum point 40 will tend to shear off tab 46 from bracket 36 rather than lifting bracket 36 away from the brick and mortar.
Similarly, if the user lifts the right hand end 48 of bracket 50, joint 52 between brackets 50 and 54 become a fulcrum point. Bottom side wall 56 of bracket 50 is a large lever which will cause tabs 58 from bracket 36 to shear off. There is not enough strength in tabs 58 to use the lever action of the side wall 56 rotating about fulcrum point 52 to lift bracket 36 away from the brick and mortar to which bracket 36 is adhering. Accordingly, a user will find in trying to strip the polarized brackets of the prior art away from the finished wall, that unless extreme care and a slow pace is used to peel brackets, the brackets will shear off tabs in adjacent brackets and each bracket must be removed one by one from the wall.